I've read forums saying it's a defective graphics chip to CPU problem and I've done steps that fix it temporarily such as chkdsk /f /r or SFC /SCANNOW in command prompt they seem to work but when my laptop goes to sleep and I wake it back up it happens again. My laptop is a Dell Inspirion 3567, specs are Intel i3-7000u and 12gb 2133 ram and 128gb ssd and graphics chip Intel HD 620. I often play games using a external drive on it along with a laptop cooling pad and wireless mouse. If anyone knows any way to fix it permanently it would be most appreciated.